<?php
	/**
	* Global Search Engine for Moodle
	*
	* @package search
	* @category core
	* @subpackage search_engine
	* @author Michael Champanis (mchampan) [cynnical@gmail.com], Valery Fremaux [valery.fremaux@club-internet.fr] > 1.8
	* @date 2008/03/31
	* @license http://www.gnu.org/copyleft/gpl.html GNU Public License
	*
	* Asynchronous adder for new indexable contents
	*
	* Major chages in this review is passing the xxxx_db_names return to
	* multiple arity to handle multiple document types modules
	*/
	
	/**
	* includes and requires 
	*/
	require_once('../config.php');

/// makes inclusions of the Zend Engine more reliable
	$separator = (array_key_exists('WINDIR', $_SERVER)) ? ';' : ':' ;
	ini_set('include_path', $CFG->dirroot.'/search'.$separator.ini_get('include_path'));

	require_once("$CFG->dirroot/search/lib.php");
	require_once("$CFG->dirroot/search/indexlib.php");	

/// checks global search activation
	
	require_login();
	
	if (empty($CFG->enableglobalsearch)) {
		error(get_string('globalsearchdisabled', 'search'));
	}
	
	if (!has_capability('moodle/site:doanything', get_context_instance(CONTEXT_SYSTEM))) {
		error(get_string('beadmin', 'search'), "$CFG->wwwroot/login/index.php");
	} 
	
/// check for php5 (lib.php)

	try {
		$index = new Zend_Search_Lucene(SEARCH_INDEX_PATH);
	} catch(LuceneException $e) {
		mtrace("Could not construct a valid index. Maybe the first indexation was never made, or files might be corrupted. Run complete indexation again.");
		return;
	}
	$dbcontrol = new IndexDBControl();
	$addition_count = 0;
	$startindextime = time();
	
	$indexdate = $CFG->search_indexer_run_date;
	
	mtrace('Starting index update (additions)...');
	mtrace('Index size before: '.$CFG->search_index_size."\n");
	
/// get all modules
	if ($mods = get_records_select('modules')) {
	
/// append virtual modules onto array

	$mods = array_merge($mods, search_get_additional_modules());
		foreach ($mods as $mod) {
			//build include file and function names
			$class_file = $CFG->dirroot.'/search/documents/'.$mod->name.'_document.php';
			$db_names_function = $mod->name.'_db_names';
			$get_document_function = $mod->name.'_single_document';
			$get_newrecords_function = $mod->name.'_new_records';
			$additions = array();
			
			if (file_exists($class_file)) {
				require_once($class_file);
				
				//if both required functions exist
				if (function_exists($db_names_function) and function_exists($get_document_function)) {
					mtrace("Checking $mod->name module for additions.");
					$valuesArray = $db_names_function();
					if ($valuesArray){
						foreach($valuesArray as $values){
							$where = (!empty($values[5])) ? 'AND ('.$values[5].')' : '';
							$itemtypes = ($values[4] != '*' && $values[4] != 'any') ? " AND itemtype = '{$values[4]}' " : '' ;
							
							//select records in MODULE table, but not in SEARCH_DATABASE_TABLE
							$table = SEARCH_DATABASE_TABLE;
							$query = "
								SELECT 
									docid,
									itemtype 
								FROM 
									{$CFG->prefix}{$table}
								WHERE 
									doctype = '{$values[1]}'
									$itemtypes
							";
							$docIds = get_records_sql_menu($query, array($mod->name));
							$docIdList = ($docIds) ? implode("','", array_keys($docIds)) : '' ;
							
							$query =  "
								SELECT id, 
									{$values[0]} as docid 
								FROM 
									{$CFG->prefix}{$values[1]} 
								WHERE 
									id NOT IN ('{$docIdList}') AND 
									{$values[2]} > {$indexdate}
									$where
							";
							$records = get_records_sql($query);
							
							// foreach record, build a module specific search document using the get_document function
							if (is_array($records)) {
								foreach($records as $record) {
									$add = $get_document_function($record->docid, $values[4]);
									// some documents may not be indexable
									if ($add)
										$additions[] = $add;
								} 
							} 
						} 
						
						// foreach document, add it to the index and database table
						foreach ($additions as $add) {
							++$addition_count;
							
							// object to insert into db
							$dbid = $dbcontrol->addDocument($add);
							
							// synchronise db with index
							$add->addField(Zend_Search_Lucene_Field::Keyword('dbid', $dbid));
							
							mtrace("  Add: $add->title (database id = $add->dbid, moodle instance id = $add->docid)");
							
							$index->addDocument($add);
						} 
					}
					else{
						mtrace("No types to add.\n");
					}
					mtrace("Finished $mod->name.\n");
				} 
			} 
		} 
	} 
	
/// commit changes

	$index->commit();
	
/// update index date and size

	set_config("search_indexer_run_date", $startindextime);
	set_config("search_index_size", (int)$CFG->search_index_size + (int)$addition_count);
	
/// print some additional info

	mtrace("Added $addition_count documents.");
	mtrace('Index size after: '.$index->count());

?>